1 files changed, 72 insertions, 27 deletions

diff --git a/src/gui/opengl/qopenglfunctions.cpp b/src/gui/opengl/qopenglfunctions.cpp
index 99604ca8b2..d436fd45ec 100644
--- a/src/gui/opengl/qopenglfunctions.cpp
+++ b/src/gui/opengl/qopenglfunctions.cpp
@@ -3193,65 +3193,105 @@ static void QOPENGLF_APIENTRY qopenglfResolveVertexAttribPointer(GLuint indx, GL
 
 #endif // !QT_OPENGL_ES_2
 
+// Functions part of the OpenGL ES 3.0+ standard need special handling. These,
+// just like the 2.0 functions, are not guaranteed to be resolvable via
+// eglGetProcAddress or similar. Calling them directly is, unlike the 2.0
+// functions, not feasible because one may build the binaries on a GLES3-capable
+// system and then deploy on a GLES2-only system that does not have these
+// symbols. Until ES3 gets universally available, they have to be dlsym'ed.
+
+Q_GLOBAL_STATIC(QOpenGLES3Helper, qgles3Helper)
+
+QOpenGLES3Helper::QOpenGLES3Helper()
+{
+#ifdef Q_OS_WIN
+#ifdef QT_DEBUG
+    m_gl.setFileName(QStringLiteral("libGLESv2"));
+#else
+    m_gl.setFileName(QStringLiteral("libGLESv2d"));
+#endif
+#else
+    m_gl.setFileName(QStringLiteral("GLESv2"));
+#endif
+    if (m_gl.load()) {
+        MapBufferRange = (GLvoid* (QOPENGLF_APIENTRYP)(GLenum, qopengl_GLintptr, qopengl_GLsizeiptr, GLbitfield)) m_gl.resolve("glMapBufferRange");
+        UnmapBuffer = (GLboolean (QOPENGLF_APIENTRYP)(GLenum)) m_gl.resolve("glUnmapBuffer");
+        BlitFramebuffer = (void (QOPENGLF_APIENTRYP)(GLint, GLint, GLint, GLint, GLint, GLint, GLint, GLint, GLbitfield, GLenum)) m_gl.resolve("glBlitFramebuffer");
+        RenderbufferStorageMultisample = (void (QOPENGLF_APIENTRYP)(GLenum, GLsizei, GLenum, GLsizei, GLsizei)) m_gl.resolve("glRenderbufferStorageMultisample");
+
+        GenVertexArrays = (void (QOPENGLF_APIENTRYP)(GLsizei, GLuint *)) m_gl.resolve("glGenVertexArrays");
+        DeleteVertexArrays = (void (QOPENGLF_APIENTRYP)(GLsizei, const GLuint *)) m_gl.resolve("glDeleteVertexArrays");
+        BindVertexArray = (void (QOPENGLF_APIENTRYP)(GLuint)) m_gl.resolve("glBindVertexArray");
+        IsVertexArray = (GLboolean (QOPENGLF_APIENTRYP)(GLuint)) m_gl.resolve("glIsVertexArray");
+
+        TexImage3D = (void (QOPENGLF_APIENTRYP)(GLenum, GLint, GLint, GLsizei, GLsizei, GLsizei, GLint, GLenum, GLenum, const GLvoid *)) m_gl.resolve("glTexImage3D");
+        TexSubImage3D = (void (QOPENGLF_APIENTRYP)(GLenum, GLint, GLint, GLint, GLint, GLsizei, GLsizei, GLsizei, GLenum, GLenum, const GLvoid *)) m_gl.resolve("glTexSubImage3D");
+        CompressedTexImage3D = (void (QOPENGLF_APIENTRYP)(GLenum, GLint, GLenum, GLsizei, GLsizei, GLsizei, GLint, GLsizei, const GLvoid *)) m_gl.resolve("glCompressedTexImage3D");
+        CompressedTexSubImage3D = (void (QOPENGLF_APIENTRYP)(GLenum, GLint, GLint, GLint, GLint, GLsizei, GLsizei, GLsizei, GLenum, GLsizei, const GLvoid *)) m_gl.resolve("glCompressedTexSubImage3D");
+
+        if (!MapBufferRange || !GenVertexArrays || !TexImage3D)
+            qFatal("OpenGL ES 3.0 entry points not found");
+    } else {
+        qFatal("Failed to load libGLESv2");
+    }
+}
+
+static inline bool isES3()
+{
+    QOpenGLContext *ctx = QOpenGLContext::currentContext();
+    return ctx->isOpenGLES() && ctx->format().majorVersion() >= 3;
+}
+
 static GLvoid *QOPENGLF_APIENTRY qopenglfResolveMapBuffer(GLenum target, GLenum access)
 {
-#ifdef QT_OPENGL_ES_3
     // It is possible that GL_OES_map_buffer is present, but then having to
     // differentiate between glUnmapBufferOES and glUnmapBuffer causes extra
     // headache. QOpenGLBuffer::map() will handle this automatically, while direct
     // calls are better off with migrating to the standard glMapBufferRange.
-    if (QOpenGLContext::currentContext()->format().majorVersion() >= 3) {
+    if (isES3()) {
         qWarning("QOpenGLFunctions: glMapBuffer is not available in OpenGL ES 3.0 and up. Use glMapBufferRange instead.");
         return 0;
-    } else
-#endif
-    RESOLVE_FUNC(GLvoid *, ResolveOES, MapBuffer)(target, access);
+    } else {
+        RESOLVE_FUNC(GLvoid *, ResolveOES, MapBuffer)(target, access);
+    }
 }
 
 static GLvoid *QOPENGLF_APIENTRY qopenglfResolveMapBufferRange(GLenum target, qopengl_GLintptr offset, qopengl_GLsizeiptr length, GLbitfield access)
 {
-#ifdef QT_OPENGL_ES_3
-    if (QOpenGLContext::currentContext()->format().majorVersion() >= 3)
-        return ::glMapBufferRange(target, offset, length, access);
+    if (isES3())
+        return qgles3Helper()->MapBufferRange(target, offset, length, access);
     else
-#endif
-    RESOLVE_FUNC(GLvoid *, 0, MapBufferRange)(target, offset, length, access);
+        RESOLVE_FUNC(GLvoid *, 0, MapBufferRange)(target, offset, length, access);
 }
 
 static GLboolean QOPENGLF_APIENTRY qopenglfResolveUnmapBuffer(GLenum target)
 {
-#ifdef QT_OPENGL_ES_3
-    if (QOpenGLContext::currentContext()->format().majorVersion() >= 3)
-        return ::glUnmapBuffer(target);
+    if (isES3())
+        return qgles3Helper()->UnmapBuffer(target);
     else
-#endif
-    RESOLVE_FUNC(GLboolean, ResolveOES, UnmapBuffer)(target);
+        RESOLVE_FUNC(GLboolean, ResolveOES, UnmapBuffer)(target);
 }
 
 static void QOPENGLF_APIENTRY qopenglfResolveBlitFramebuffer(GLint srcX0, GLint srcY0, GLint srcX1, GLint srcY1,
                        GLint dstX0, GLint dstY0, GLint dstX1, GLint dstY1,
                        GLbitfield mask, GLenum filter)
 {
-#ifdef QT_OPENGL_ES_3
-    if (QOpenGLContext::currentContext()->format().majorVersion() >= 3)
-        ::glBlitFramebuffer(srcX0, srcY0, srcX1, srcY1, dstX0, dstY0, dstX1, dstY1, mask, filter);
+    if (isES3())
+        qgles3Helper()->BlitFramebuffer(srcX0, srcY0, srcX1, srcY1, dstX0, dstY0, dstX1, dstY1, mask, filter);
     else
-#endif
-    RESOLVE_FUNC_VOID(ResolveEXT | ResolveANGLE | ResolveNV, BlitFramebuffer)
-        (srcX0, srcY0, srcX1, srcY1, dstX0, dstY0, dstX1, dstY1, mask, filter);
+        RESOLVE_FUNC_VOID(ResolveEXT | ResolveANGLE | ResolveNV, BlitFramebuffer)
+            (srcX0, srcY0, srcX1, srcY1, dstX0, dstY0, dstX1, dstY1, mask, filter);
 }
 
 static void QOPENGLF_APIENTRY qopenglfResolveRenderbufferStorageMultisample(GLenum target, GLsizei samples,
                                       GLenum internalFormat,
                                       GLsizei width, GLsizei height)
 {
-#ifdef QT_OPENGL_ES_3
-    if (QOpenGLContext::currentContext()->format().majorVersion() >= 3)
-        ::glRenderbufferStorageMultisample(target, samples, internalFormat, width, height);
+    if (isES3())
+        qgles3Helper()->RenderbufferStorageMultisample(target, samples, internalFormat, width, height);
     else
-#endif
-    RESOLVE_FUNC_VOID(ResolveEXT | ResolveANGLE | ResolveNV, RenderbufferStorageMultisample)
-        (target, samples, internalFormat, width, height);
+        RESOLVE_FUNC_VOID(ResolveEXT | ResolveANGLE | ResolveNV, RenderbufferStorageMultisample)
+            (target, samples, internalFormat, width, height);
 }
 
 static void QOPENGLF_APIENTRY qopenglfResolveGetBufferSubData(GLenum target, qopengl_GLintptr offset, qopengl_GLsizeiptr size, GLvoid *data)
@@ -3506,4 +3546,9 @@ QOpenGLExtensionsPrivate::QOpenGLExtensionsPrivate(QOpenGLContext *ctx)
     DiscardFramebuffer = qopenglfResolveDiscardFramebuffer;
 }
 
+QOpenGLES3Helper *QOpenGLExtensions::gles3Helper()
+{
+    return qgles3Helper();
+}
+
 QT_END_NAMESPACE